05/31/2023
On this Teamwork Tuesday, we present a case that highlights the work of Rhinebeck Equine’s Surgery and Internal Medicine teams, along with the referring vet from Equine Clinic at OakenCroft and an experienced farrier to manage a mare with laminitis, PPID (Pars Pituitary Intermedia Disorder/Cushing’s Disease), and EMS (Equine Metabolic Synrome).
A 23yo Morgan mare, was referred by Dr. Suzanne Jaynes from ECO for management of acute laminitis and suspected EMS. The mare had been noted to be lying down more the last few days before coming up acutely lame. Dr. Jaynes’ exam revealed bounding digital pulses in all 4 feet, sensitivity to hoof testers, and rotation of the coffin bone in all 4 limbs on radiographs. The mare was noted to have a cresty neck and fat deposits around the tail head, signs of EMS.
On admission to Jesse Tyma, DVM, DACVS, the mare had an increased heart rate and walked tentatively. The mare was placed in soft rides on all four feet. The mare was managed for suspected endocrinopathic laminitis and was started on a low starch diet, Platinum Performance Metabolic Support, InsulinWise, Thyro-L, and multimodal pain medications.
The mare was assessed by Laura Javsicas, VMD, DACVIM for endocrine disorders. A TRH stim was performed to test for PPID and a baseline fasted insulin test was performed. The baseline ACTH was normal but the ACTH after administration of TRH was elevated, consistent with a diagnosis of PPID. The fasted baseline insulin was above 40, consistent with a diagnosis of EMS.
Under radiographic guidance, farrier Hilary Cloos placed wooden clogs on the mare’s front feet to change her biomechanics and improve comfort. After the clogs were placed, her comfort and heart rate slowly normalized. Radiographs were obtained throughout hospitalization to monitor the progression of laminits.
EMS is a disorder associated with the inability to regulate blood insulin levels resulting in hyperinsulinemia. PPID is the development of benign tumors of the pituitary gland which is responsible for regulating the body’s hormones including ACTH (adrencorticotropic). Both disorders can lead to insulin dysregulation, which can cause laminits particularly when exposed to a diet high in non-structutal carbohydrates such as spring grass.
Management of these disease processes through medications, diet, and farrier care are key to maintaining comfort and health. If your horse is obese, has regional fat deposits, ring on their hooves, and/or is one of the breeds predisposed to EMS (Morgans, Paso Finos, Mustangs, Warmboods, ponies, and donkeys) talk to your vet about appropriate testing and treatment before they develop signs of laminitis.
